Oligomer physical constants

Naarmann et al. used exactly the same reactions to synthesize the whole series of a-oligothiophenes up to H—Tg-H 6. No yields are given, but the authors paid very much attention to the purification procedure and the physical constants of the various thiophene oligomers [12]. The use of iodo compounds proved to be even more effective, since H—T2—H 2 was obtained by the nickel-catalyzed coupling [Ni(dppe)Cl2] of I—Tj—H 8 and its Grignard derivative in 90% yield [78]. 

Notably, the actual chemical reaction is factored out, as the same bonds are broken and formed in both the intra- and intermolecular reactions. The EM has units of mol L, and is not always a physically attainable concentration. However, for most RCM reactions, the attainment of high reaction concentrations does not represent a problem as most are far less efficient. The EM represents the reaction concentration at which a 1 1 mixture of cycloaUcene and oligomer would be expected i.e. the concentration at which the intra- and intermolecular reactions occur at the same rate (for EM) or with the same equilibrium constant (for EMx). Therefore, in order to avoid deleterious oligomerization processes, metathesis reactions should be conducted at a concentration of approximately a tenth to a hundredth of EM (or EMx). 

This Handbook summarizes in ten chapters all aspects of oligo- and polythiophenes as they developed over the last twenty years, from chemistry to physics and applications. It has been written by the most reknown experts in the field worldwide, from both academics and industrial origins, with a constant care of clarity through concise texts and an extensive use of figures and tables. This first review on PTs and oligomers constitutes a comprehensive tool not only for researchers but also for advanced students and anyone willing to get informations on this novel class of materials. 

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